Caption: Titanosaurus dinosaur egg fossils. Fossils appear as rock slowly forms around objects buried in mud. As the rock forms, the shape and anatomy of buried animals and plants can be preserved, including secondary structures such as eggs. Titanosaurus was a large sauropod dinosaur that lived some 65 to 70 million years ago during a stage of the Upper Cretaceous. These egg fossils were found in Provence, France.